Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef904ed798748d7d…

MALICIOUS

PDF

83.9 KB Created: 2021-07-19 17:36:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 34adfb10dffe3d996b1f6a0b588964df SHA-1: 380d2f2adfcb113bc76add359dcc872b105e1eea SHA-256: ef904ed798748d7d0c726f016b609ef7b4eb13a21a1b98b2cc2444b5883e6130
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised WordPress sites and appear to form a link farm. The presence of these links suggests an attempt to lure users to external malicious resources, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://interstyle.org/content/xuploadimages/file/2324264036.pdf In PDF document text
    • http://fantalife.nl/userfiles/file/23197653159.pdfIn PDF document text
    • https://ercrs.org/wp-content/plugins/super-forms/uploads/php/files/fvfop7a7gt76dmos80k2jace0o/xubopilawifubipapapu.pdfIn PDF document text
    • https://aashianarealty.com/file/kimutuwinosojofilu.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ef3be376d8---goramo.pdfIn PDF document text
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160e86bab18ad7---jinasavatepigibesulorisa.pdfIn PDF document text
    • http://www.clc-engineering.com/siteuploads/editorimg/file/zobatimulotofesidarugal.pdfIn PDF document text
    • https://www.wflorlando.com/wp-content/plugins/super-forms/uploads/php/files/c94c08dc0c9142de138e464c4ff18dc8/15345746636.pdfIn PDF document text
    • http://ngpsusa.com/wp-content/plugins/super-forms/uploads/php/files/9siiucjs8kds95093onbih4lq5/10228284079.pdfIn PDF document text
    • http://lbs.ac.at/wp-content/plugins/super-forms/uploads/php/files/q1e6lmnjass8h20c2haq4r876k/vapolawewenipe.pdfIn PDF document text
    • https://helicopterleasingservices.com/userfiles/files/5290996670.pdfIn PDF document text
    • https://inverpalmas.com/aym_image/files/wevuv.pdfIn PDF document text
    • http://www.loockuniformes.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/160a5f17169410---kanumumumer.pdfIn PDF document text
    • https://pet-fashion.ro/mm/file/12737204741.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/ro3e7mulq7ma9k20ore1t8p00m/rufuge.pdfIn PDF document text
    • http://bensonhigh67.com/clients/55910/File/28644678320.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606fd7c9314ab---29596589178.pdfIn PDF document text
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/160bab012c6e69---rejuvawej.pdfIn PDF document text
    • http://residencecarlofelice.com/userfiles/files/kajofirerufikenugedaf.pdfIn PDF document text
    • https://naucharts.com/ckfinder/userfiles/files/zumazoxulewubefogopejela.pdfIn PDF document text
    • http://crystalnymph.by/wp-content/plugins/super-forms/uploads/php/files/1fbf13a074824629bfc4fc52db6a6134/72082339318.pdfIn PDF document text
    • https://chmelo.hu/sites/default/files/file/mimipusimidaz.pdfIn PDF document text
    • http://www.pianoszimmermann.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160711d3c1d3da---fojokalizowajonuxazu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=how+to+type+exponents+in+powerpointPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e646.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE646 10332 bytes
SHA-256: e3f34ce1c5f4d41da137373b63f470eef31e49a1456d238b948d719fb08d6e60
font_01_sfnt_off0000fdc4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDC4 17020 bytes
SHA-256: fab5a4088e2e0de0806330e16a2e16b91c23ee59bd185baca764837a50165821
font_02_sfnt_off00012a2f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A2F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1